I don't mind the negative comments on my plans. I know alot of people wouldn't do this and that's why I have already made up my mind that I am going to do this mod and I just want tips and more info on the fueling stuff.

Positive or Negative comments are welcome

 

He said in his first post the car is a 4+3, but it doesn't matter: all '84s were D36's, the D44 didn't show up until '85.

 

HP divide it by 14.7(NA) then multiply by 19.7.
19.7 = 14.7 + 5 PSI


If you have 205 hp then 205/14.7
13.9455782 x 19.7 = 274.727891

74 hp gain

are you still doing it ?

 

Thanks for the math man and yes Im still going to do it. Just a matter of figuring out the fuel stuff and seeing what needs to be upgraded

 

You're welcome ! Good Luck on your project,i will keep a close eye !
Btw ..how much $$$ are you spending,ballpark...

 

Your 4+3 will be fine at 300+ HP if it's in good shape. 8-ish psi will be fine on the '84's stock internals provided you fuel it correctly. I'm not sure what injectors they used in the cross fire, but I think they're similar to TBI, and instead of 2 you have 4. My boat has 2 75#'ers (same as 454 pickups), and I push 315hp with those. Working with the '84 ECU will be challenging. I suggest adding auxillary injectors like Callaway did. Use something like the additional injector controller (AIC1) at www.splitsec.com.

 

84 is forgeed and with gears headers, ETC you can probabaly pick up a couple of seconds atleast.

There is an article somewhere of an 84 that was sooped up cheap and nitrous and now a fast car.
just google it.

unless you have plenty of money tools and fab potential then change everything out and twin turbo it.

 

Not to hijack this thread from the OP, my twin turbo kit came with an AIC and two additional injectors. But seeing as 20 some odd years has passed and you can get larger injectors anyways, I was thinking about just installing larger injectors and using something like the Apex-i SAFC to tune them. Maybe on the CFI engine you could do the same.

 

While you seem set to start on this project and I hope it works for you, I don' think you have answered one pretty basic question: What experience do you have working on cars? Have you done any engine rebuilds or even did an R&R on a C4 Corvette engine?

I guess what I 'm trying to point out is that while doing a turbo install can be a great learning experience, if the basic engine is not up to the task of handling a big increase in power, there is a distinct possibility of finding pieces of metal and fluid on the ground along with possibly having large cooling holes in the block And with 125K miles on the engine in your car, that's more of a reality than a possibility.

I would suggest that you first concentrate on doing a rebuild of the motor. Concentrate on quality parts for the bottom end. Good bearings, proper machine work based on the mods you want to do, the correct pistons and rings to support the boost levels anticipated, and a suitable cam.

You have to consider the necessary cylinder head work too; valve springs to match the cam, rocker arms that will work with the cam specs, port matching of the intake, and finally proper assembly of the entire engine. The 84 iron heads may be OK to start, but later aluminum heads will provide a much better base for building power.

Once you have a foundation that will handle power increases, then you can start the planning for the turbos.

 

Eilax,listen to cruiser,he knows what he is talking about
when i first rebuild my engine i came here 2 years ago and i felt like
all the guys here didn't want to help me or they keep turning my ideas down, i follow their advices,because what they say is because they have been there and they are giving you the shortcuts,and making you avoid a terrible failure ! There is no way your engine with 125K will live longer,i had to rebuild it 2 years ago with 126K ...and when i first got here i started asking for 500 hp and wanted more power...i rebuild it healthy and mild,now 2 years later i got rid of my stock heads/intake and zz4 cam and just now i want some more.-



This picture was taken the day i knew i had to rebuild.-
My bet is REBUILD healthy first,then turbocharge it !

 

I agree with rebuild and then go apecrap on mods. 350's are dirt cheap to rebuild since they are so common.

 

I gotta disagree with the recommendation to build a new engine prior to the turbo work. I would start the fabrication/installation of the turbo plumbing with the current engine. This lets the builder find out (cheaply) what interference issues there are. Also, once the setup is completed, the low speed/low power drivability calibrations can be done on a "cheap" engine, and any gross (damaging) calibration errors or spark/fueling equipment failures will be limited to an engine that is scheduled to be rebuilt anyway, rather than risking a freshly built (expensive) engine.

 

I sooo agree with this approach. I also think that he should go for it, if his engine blows the first day, is he really out anything? Unless of course he takes something out that he just purchased, which is unlikely. And so if he has to do something over, or 2 or 3 times, that just helps the learning process even more. I say DO IT and tell us all about it during the process. If you have some success, go get the parts to make it bulletproof and then turn the dial up to 11 on that old, stock motor and videotape its destruction! Reminds me of the good ol' days when we would strip down a 2.2 turbo car like a Lebaron or New Yorker and rig the wastegate to not open until about 16 pounds of boost and try to break it. There was a article in Mopar Action called "12 seconds for 1200 bucks". Great fun.

 

69427 has an excellent point !!!
i haven't thought about it !
But this is from the experimental point of view only.-
Yes its a insurance or test mule engine before the real one to make sure the turbo works
i like it !

But after that ...a rebuild is a must !

 

The reason I would disagree with going ahead on the existing engine is that the OP states the car is his daily driver. It will be hard enough to have the car down to do the initial design, fabrication, installation and basic tuning if he doesn't have another car to use in the interim.

And if the motor goes TU because of a catastrophic failure due to the HP increase, he will be without a car that much longer. And deeper into his wallet. At least with a rebuild or some sort of fresh motor, he will still have a car that will run strong and be dependable.

And he still hasn't commented about his experience level with regard to working on the C4, much less a budget level.

 

why people want to do these kinda mods without a back up car is beyond me. Talk about stress!

 

next week i am going to start on building a rocketship to fly to the moon.. i have no engineering background or idea of flight and its principals or propulsion. but i got $20 and i think i can make it happen.. wish me luck..

 

I just don't agree with your logic.

 

I have a lot of experience with cars, Especially the 84 vette. When I bought my car I needed to do a major overhaul on it. I have since I bought it got it running, new interior, I am going to lower it, redid the clutch, installed headers and exhaust. As of now my car is not my daily driver. It will be as soon as I get it insured. I have also did worked with my brother restoring his 84 that had a bent frame and practically no front end. My dad is also a very experience man who has done many restoration jobs and has alot of experience with welding/fabrication. Between the three of us there is an abundant amount of experience to get this job done.

 

I'm expecting my engine to last a little bit with a low boost level without doing work to it but I am being realistic and going into this project with in mind that my engine can go at any given moment.